Concrete tunnel shuttering unit - has hinging arm of adjusting mechanism formed by one arm of cantilever

摘要

The tunnel shuttering unit is for structures of concrete and reinforced concrete, and has hinging stiffening struts coupled to both roof and wall sections and lever drive mechanisms acting between the latter. Each mechanism has a hinging arm between wall and roof section and spanning the angle between them, together with an adjusting drive. The hinging arm(6) forms one arm of a cantilever(7), whose other arm(8) extends past the coupling point(9) of the hinging arm to form an adjusting arm, to which the adjusting drive is coupled. The cantilever can be formed by a single or double triangular metal plate, with the hinge axes(10-12) at the corners.